The bill, which passed the House nearly three weeks ago, now heads to President Barack Obama, who has pledged to sign the bill.

His signature will ultimately end the government’s indiscriminate collection of millions of Americans’ phone metadata, requiring the government obtain a targeted warrant to access the data instead.

The vote came two days after Senate Majority Leader Mitch McConnell begrudgingly moved to vote on the USA Freedom Act after pressure from House Republicans, the Obama administration and staunch reform advocates in the Senate, like Kentucky Sen. Rand Paul, who helped force the expiration of the Patriot Act provisions late Sunday.

McConnell had hoped to fully reauthorize the Patriot Act, which would have kept in place more broad information gathering powers for the NSA. The USA Freedom Act is seen as a compromise measure that offers some reforms.

Two weeks ago, Paul led a 10-hour stand against the Patriot Act and the NSA domestic spying powers the law authorizes. He voted against the USA Freedom Act, which he has claimed does not go far enough in reforming the intelligence agency.

The legislation requires the government obtain a targeted warrant to collect phone metadata from telecommunications companies, makes the Foreign Intelligence Surveillance Court (known as the FISA court) which reviews those warrant requests more transparent and reauthorizes Patriot Act provisions that lapsed early Monday.

But McConnell painted the vote as one that would “take one more tool away from those who defend this country every single day.”

He slammed the bill in a speech on the Senate floor before the vote on Tuesday, but only went after President Barack Obama in his criticism, leaving out Senate and House Republicans who supported and led reform efforts.

“This bill is part of a pattern going back to the time the President took office to pull back,” McConnell said. “This is a step in the wrong direction.”

Senate passage on Tuesday came only after members defeated a series of amendments pushed by Senate Republican leaders they said would toughen the House version.

That move drew heavy fire from supporters of the current bill and from GOP House leadership, who warned the proposed changes wouldn’t pass muster in the House.

“We were not going to simply rollover and accept the House bill without debating it and attempting to amend it,” McConnell said Tuesday afternoon. “There are a number of us who feel very strongly that this is a significant weakening of the tools that were put in place after 9/11.”

House warns against amendments

House Majority Leader Kevin McCarthy warned the Senate on Tuesday morning those amendments would make it “a real challenge” to pass the bill in the House.

“I think the best approach, at the time and place we are now, and one that guarantees that we can get a bill to the president, is to pass the USA Freedom Act,” the No. 2 House Republican said Tuesday.

McCarthy’s Democratic counterpart, House Minority Whip Steny Hoyer of Maryland, said major changes from the Senate would pose a problem in the House, pointing to a “pretty broad ideological spectrum” of House members opposing Senate amendments.

“It’s a shame Senator McConnell waited so long (to move the House bill),” Hoyer said.

The chief Republican sponsors of the USA Freedom Act in the House and Senate are strongly pushing back against any changes too, with Sen. Mike Lee of Utah calling those amendments “poison pills.”

Rep. Jim Sensenbrenner of Wisconsin, the chief sponsor in the House, also called changes “a poison pill” Tuesday morning during a House GOP conference meeting, according to a Republican who attended the meeting.

Senate on different frequency

But Senate Majority Whip John Cornyn said while he is “always worried” about having the votes he needs, he was hopeful amendments to the USA Freedom Act would pass.

“What I’m hearing people say is that the amendments produce good policy and they actually strengthen the underlying bill but we’re afraid the House will not take any changes, which is just absolutely an abdication of the Senate’s role as a co-equal branch of the legislature,” he said.

And he called it a “trumped up idea” that the House would dismiss a Senate-amended version of the USA Freedom Act.

Sen. John Thune agreed, saying he didn’t believe the Senate amendments, which he supports, would endanger House passage, suggesting the House warnings were more bluster than anything.

“If some of these amendments end up getting added, I don’t think it should in any way change the ultimate outcome or what the House‎ does,” he said. “I think there’s a difference between what they’re saying right now. They’re trying to keep pressure on and keep their bill clean.”

Any changes in the Senate would require the bill go back to the House for another vote, while passage of an identical bill could go straight to President Barack Obama, who has urged the Senate to pass the USA Freedom Act.

And Sen. Dianne Feinstein, the top Democrat on the intelligence committee, said that process would cause too long of a lapse in the country’s counterterrorism capabilities.

“I think the national security interest of the United States is really best served if we get the program up and running, with the House formula, which is what the president wants. We can amend it later on,” she said. “The most important thing is having functioning tools that can be used. ‎I have never seen a time of greater potential danger than right now and I’ve never said that before. So to take away these tools at this time I think is a big mistake.”

The amendment

But intelligence committee chairman Richard Burr, who with McConnell initially sought out a straight reauthorization of the Patriot Act, is looking to get amendments added to the House bill he says would help assuage security concerns.

As telecom companies would hold onto the phone data, instead of the government, under the new legislation, the most popular leadership-backed amendment would make two changes. It would force the phone companies give the government six months notification if they plan to change their data retention policies. Another would require the Director of National Intelligence greenlight the new collection system.

Paul had also planned to offer up his own set of amendments that would push Freedom Act reforms to the NSA even further. Paul ultimately will not get a vote on his amendments, though, but said he will not press his case.

“I think we’re about done,” he said when asked if he would hold up final passage.

But any changes out of the Senate would galvanize Paul’s allies in the House who have said amendments would prompt them to offer up changes of their own.

“If even one comma changes, we have a lot of people on our side of the Capitol who would like to offer our own amendments,” Amash said.

Amash insisted that members across the House Republican conference believe “any changes will be a deal breaker.”